Quality Assurance in Histopathology

Dr Dinah V ParumsM.A.,PhD,B.M.,B.Ch.,FRCPath.,FCCP

Consultant Histo/Cytopathologist, 2001U.K.

Objectives Satisfy RCPath requirements:

Trainees will have some knowledge of QC, QA, CQI and professional QA as applied to Anatomic/Surgical Pathology

Success at Royal College exams Enjoy a safe professional practice Prepare for lab management role

QA in AP

QA program structure Driving forces CPA general requirements Local reporting structure

Core QA elements Autopsy Cytology Surgical Pathology

Introduction to error management in anatomic pathology

QA: driving forces Mandated for lab accreditation

Accreditation: CPA Assessment: EQA

Financial Incentive Cancer Unit/Centre status Coroner’s Office requirements

Medical “standard of care” Litigation protection (CMPA) Complaint/license protection (CPSO) Hospital privileges

Technical “good lab practices”

Clinical Pathology Accreditation (CPA) Specifies general organizational

structure of Lab QA program (quality manager, manuals)

Extensive documentation requirements Personnel qualifications & training Equipment, reagents, supplies Communications & LIS Specimen handling & reporting

Etc.

CPA QA requirements General (apply to all lab areas)

“appropriate quality indicators monitored…” “QC processes shall consist of goals, policies,

procedures, tolerance limits and corrective actions…”

[labs] “shall establish clinically appropriate turnaround times for each examination”

Specific (apply to individual labs) Practice standards (e.g. surgical path specimen

containers shall have adequate volume of fixative)

Activities (e.g. HSIL pap/histology correlation)

Core QA elements: Autopsy TAT monitored weekly and audited semi-

annually (std 80% in 8 wks, max. 10 wks) Case rounds (aut conf, MMR, ML rds) Provincial centralized forensic case review CPA requirements

Consent, identification, paperwork Block & slide retention times (20yrs adult, 50

yrs child) Report to include gross, micro, major findings,

information needed to determine cause of death

Core QA elements: Cytology CPA mandated activities

Overdue case tracking 10% negative pap’s rescreened before sign-out

(targeted and random) 3 yr back rescreen for new HSIL+ Cyto-histo correlation (pap HSIL, non-gyne) Diagnostic category rates (neg, ascus, sil) TAT (monitored semi-annually, 2wks for paps, 3

days for non-gyne) False negative rate (rescreen SIL : initial neg)

EQA slide surveys

Core QA elements: Cytology CPA standards

Separate screening area Instructions for specimen collection to providers Requisitions include clinical & pap history, LMP Accepted staining methods used Contamination prevention procedures Separate gyne/non-gyne staining All paps screened by techs Techs may finalize neg/benign change only Abnormal areas marked & tech comments retained Pathologists provide feedback to techs

Core QA elements: Surg Path CPA mandated activities

Overdue case tracking TAT (monitored semi-anually, std 2

days for bx’s, 3 days for routine + extra for IP/specials)

EQA IP and special stain testing Patterns of practice surveys

Core QA elements: Surg Path “Standard of care activities”

Frozen section/final diagnosis correlation Addendum/amended correlation Mandated second review rate Case rounds/tumour board review rate

“Good lab practices” activities “Incident” reporting and tracking

labeling, pickups, no tissue, lost tissue etc Daily staining QA log Customer satisfaction surveys

Core QA elements: Surg Path CPA mandated standards

Adequate volumes of fixative Labels have name, unique ID & tissue site FS manual covers specific specimen types FS results communicated directly and recorded Addendums for special studies Appropriate IP controls IP slides kept with other case slides Log time slides delivered to pathologists Document IP slide results Pathologists evaluate slide quality List of specimens on report

Core QA elements: Surg Path CPA mandated standards (cont’d)

Report includes: gender, DOB, pt location, attending & submitting

MD, dates of procedure, accessioning & reporting Clinical history Gross description including block list FS diagnosis Microscopic as relevant Final diagnosis (indicate if gross exam only) Pathologists signature or electronic equivalent

Core QA elements: Surg Path CPA mandated standards (cont’d)

Lab has appropriate slide, block, report and tissue retention guidelines

Wet tissue 4+ wks after report issued Blocks and reports :

20 yrs for adults 50 yrs for children

Slides : 10 yrs for adults 10 yrs after 18th birthday for children

Introduction to Diagnostic Error Management in Anatomic Pathology

No generally accepted definition of what an “error” is

Definition issues include: Hindsight bias “Expert” opinion Viewpoint

Clinical: significant vs insignificant Legal: negligent vs reasonable

Error Classification Planning: wrong plan, right execution Cognitive: right plan, problem in

execution Slips & Lapses

Slip: error of commission (e.g. pick up slide from wrong case, mislabel slide)

Lapse: error of omission (e.g. miss a slide, miss a gross lesion, don’t label block, forget to include margin status in report)

Mistakes: knowledge, rule and “thought” based errors

Mistakes Lack of knowledge

Unaware of an entity, of classification or process rules

Misinterpretation of data Unable to apply good data and good

rules Application of bad rules

Inevitable disagreements resulting from bad rules considered “errors” (e.g. ASCUS)

More frequent Near misses If notice error can

recognize and fix Self corrected Very difficult to

eradicate

Less frequent May recognize a

problem but not consider it an error

Not self corrected Easier (but still

difficult) to eradicate

Slips/lapses vs Mistakes

Approaches to error management Use systems rather than person

approach Recognize human fallibility and structure

operational systems around this Safe systems

Simplify tasks, add visual cues, reduce reliance on memory

Design for reversibility and recovery Stress educational rather than punitive

environment Monitor errors and near misses and respond

Medical-legal aspects of error Malpractice

Injury resulting from negligence Negligence

Medical practice which falls below the “standard of care”

Standard of care Peer based in theory although in

practice often expert based “best practice”

Pathology malpractice Low frequency of claims

8.3% of U.S. pathologists per year: average pathologist has one claim every 12 years (compare to 55% of U.S. neurosurgeons per year)

Probably about half these rates in U.K. High success of claims High severity (cost) of claims,

particularly in U.S.

Pathology Claims Analysis

15% “random” 85% “systematic”

Mainly cancer diagoses: 63% false negative (FN), 22% false positive (FP)

Top 5 types (57% of claims) were: breast (15%) FP = FN melanoma (13%) 95% FN Pap smears (12%) 98% FN gyne (9%) 85% FN, 42% ovarian tumours operational (6%) specimen mix-ups & losses, typo’s

etc

Pathology Error Management Mandatory prospective second review

of high risk cases documented in report Retrospective review at tumour boards

and teaching rounds with case tracking Subspecialty sign-out Synoptic and template based reporting

Conclusion: QA in Histopathology Driven by

Structured accreditation requirements Unstructured expectations of good medical care

Includes Standards of lab practice Quality activities (audits, indicator monitoring) A systems based error management program

targeting high risk operational and diagnostic areas